[Preparation of bacterial outer membrane vesicles modified with anti-angiogenic peptide AP25 on the surface and...

Bacterial outer membrane vesicles (OMVs) have attracted widespread attention in the field of drug delivery due to their excellent biocompatibility, tumor penetration, and loading capacity. The anti-angiogenic peptide AP25 can block malignant tumor angiogenesis and has broad-spectrum anti-cancer activity. To achieve efficient delivery of AP25, we modified AP25 on the surface of OMVs through genetic engineering and explored their inhibitory effects on breast cancer and gastric cancer in vitro. The results indicated that the engineered OMVs had typical morphological characteristics of OMVs, and the particle size distribution conformed to the theoretical. Proteinase K digestion combined with Western blotting confirmed that AP25 was modified on the membrane surface of OMVs. Cell experiments showed that WAP25 OMVs significantly inhibited the proliferation, migration, and invasion of MDA-MB-231 and HGC-27 cells, promoted the cell apoptosis, and downregulated the expression of tumor migration and angiogenesis-related proteins: integrin beta 1 (integrin β1), Homo sapiens inhibitor of DNA binding 1 (ID1), nuclear factor kappa-B (NF-κB), and vascular endothelial growth factor (VEGF). This study achieves effective delivery of protein drugs based on OMVs for the first time, providing new ideas for the anti-angiogenesis therapy for tumors and the functional development of bacterial OMVs.